Can't move on...

I've been dealing with a relapse of my anxiety problems and I really needed somewhere to get my thoughts down and share with anyone who would listen what I've been going through. It started when I was in grade school. I developed an intense separation anxiety from my parents, especially my mom. I eventually got over the separation anxiety but developed an anxiety of going to school, where I was terrified that I would throw up at school. These were both crippling for me, but I still somehow managed to excel in sports and school. Once getting over both of these, I didn't have any major anxiety problems, besides being generally more anxious than your average person. It was difficult, but manageable.

Fast foward to present day. I just graduated from a very good Northeastern school, where I did well and settled into a routine of comfort where I generally avoided things that made me anxious. Now that I'm out of college, I'm realizing that a lot of the things I avoided are things that must be confronted in the real world, and things that I simply can't avoid anymore. The main one is being in a relationship and being sexually active. When I was in high school I met a girl that I really liked, and it was reciprocated. The first time we were together intimately I couldn't fulfill my duties as male, if you get my point. I remember being so nervous when we were escalating things that I was shaking. Because of this I was so embarrassed that I broke it off with this girl and avoided her at all costs, making her feel terrible in the process. I know from some of her friends that she was devastated and really lost a lot of self-esteem from my actions. I literally ignored her and avoided her because I was so afraid and embarrassed. At 17, I couldn't talk about it frankly with her, and I hurt her so much in the process. My anxiety didn't only hurt me, it hurt a great girl and I still haven't forgiven myself. This experience has stuck with me, very vividly, for the past 6 or 7 years. Consequently I've developed an intense anxiety of sexual intimacy and being in a serious relationship with a woman. I have had a number of opportunities with good girls to get into relationships but I'm terrified to do so. In college I had a few more bad sexual experiences, most of them involving alcohol. I also had good ones, but most of them were bad.
The ironic part of all of this is that I began seeing the girl from the high school incident frequently during my summers back home, and developed very strong feelings for her. She is intelligent, beautiful, emotional... but because of my anxiety, I could never make a move. Just this past Thursday I finally, thanks to alcohol (I don't get nervous when I'm drunk), was able to be myself around her and we ended up kissing for the first time in 5 years. I was on cloud 9 the day after, very glad my inability to act on my feelings was finally ended, but now my anxiety is kicking in terribly. I want to be in a real relationship, for the first time in my life, but I'm once again terrified to make another move. I simply don't know how to move forward. I'm depriving myself of one of the highest human experiences, that of romantic love, and I can't do anything about it. Now sitting here, I've been having mini-panic attacks because I know this is my window of opportunity with this girl and I don't want to mess it up... and I'm terrified to take action, out of fear of rejection, fear of failure, fear of sexual intimacy.
I apologize if the frank talk of my sexual anxiety offends anyone, but this is what I've had to deal with for so many years, and I so desperately want to move onto being able to actually get close to women. I'm ready to fall in love, to experience the emotion that has inspired some of the greatest feats, music, poems, and works of art in history. I want to feel the highest emotion, finally.